Spirifer is a genus of marine brachiopods belonging to the order Spiriferida and family Spiriferidae. Species belonging to the genus lived in the Carboniferous (certainly in the Tournaisian and in the Visean, possibly also in the Serpukhovian and the Bashkirian).

This genus used to be treated more widely, so less critical sources list its species from the Middle Ordovician (Sandbian) through to the Late Triassic (Carnian) with a global distribution.

Like most brachiopods, representatives of Spirifer were stationary epifaunal suspension feeders.

As Spirifer has been described early on, since then, many species have been reassigned.